Split Server (sepatarion of services) resources

[thiagolinhares]

Hello,

I'm about to deploy a "Split setup" with 3 servers (webapps | mailstore | proxy) (guide: https://wiki.zimbra.com/wiki/Separation ... _In_ZCS8.5)
Just couldn't find anywhere some documented instructions resources. Like I have an ideia of resources needed for single-servers deploy. But when splitting, which of those will demand more resources than others?

It would be awesome if someone with experience is this kind of enviroment could share it with us.

[L. Mark Stone]

Hello,

I'm about to deploy a "Split setup" with 3 servers (webapps | mailstore | proxy) (guide: https://wiki.zimbra.com/wiki/Separation ... _In_ZCS8.5)
Just couldn't find anywhere some documented instructions resources. Like I have an ideia of resources needed for single-servers deploy. But when splitting, which of those will demand more resources than others?

It would be awesome if someone with experience is this kind of enviroment could share it with us.

In my experience, that kind of split functionality never worked well.

For a large and/or highly available system, I'd recommend:
-- Two proxy servers behind a clustered load balancer
-- Two MTA servers, one for outbound webmail and IMAP client use, and for inbound (the MX). Add more if inbound mail volumes will exceed 25K emails per hour.
-- Two LDAP MMR servers (ldap_master_url, for writes)
-- Two LDAP replica server (ldap_url), for reads
-- Mailbox servers as needed

A more modest architecture for 1,000 to 25,000 active mailboxes would comprise:
-- A combined Proxy/LDAP Master server
-- A combined MTA/LDAP Replica server
-- Mailbox servers as needed, typically 1K to 6K active mailboxes per mailbox server, depending on usage

In the more modest architecture, 4 cores and 12GB of RAM for the Proxy and MTA servers is generally fine. If you allow large emails and your users send a lot of attachments, add a few more GB to your MTA servers and configure a RAM Disk for Amavis's tmp directory. For the mailbox stores, 16GB and 6 cores is a good modest size, as Zimbra scales with better performance by adding more mailbox stores as opposed to adding resources to a mailbox server.

Hope that gets you started.

All the best,
Mark

[thiagolinhares]

Hello Mark.

I really appreciate all the information you shared.
Now I have a real "start point" on how to better scale and deploy all those services.

Again, thank you!

[L. Mark Stone]

Hello Mark.

I really appreciate all the information you shared.
Now I have a real "start point" on how to better scale and deploy all those services.

Again, thank you!

You are most welcome!

Glad I could help!

All the best,
Mark

[zimico]

Thank Mark for your very helpful info.
Now Zimbra provide mmr ldap. So do we still care about setting ldap write and read manually?
Best regards,
Minh

[L. Mark Stone]

Thank Mark for your very helpful info.
Now Zimbra provide mmr ldap. So do we still care about setting ldap write and read manually?
Best regards,
Minh

Electing to deploy LDAP MMR is a one-way ticket; there is no going back.

You can also have, say, two LDAP MMR servers and multiple traditional LDAP Replica servers.

In 8.6, LDAP MMR had some issues that would cause "split brain" syndrome. That's long since fixed, but with the ephemeral database backend soon to become GA, I am recommending to deploy tradition Master-Replica now, wait until the ephemeral database backend becomes GA, deploy it, and then you can deploy LDAP MMR at that time no problem.

Regardless, the localconfig variables ldap_url and ldap_master_url still control read and write destinations, so one should load balance LDAP reads/writes anyway by adjusting the order of the LDAP servers in those variables on different mailbox servers.

Hope that helps,
Mark

[zimico]

Thank for your clarification, Mark. I don't know about this LDAP MMR concern.
Regards,
Minh.